The identity of unknown substances can be determined through a variety of means. When samples of an unknown substance can be obtained, various tests and analyses can be performed to determine the likely identity of the substance. In some instances, however, it is either not possible or not desirable to obtain samples of an unknown substance. In such cases, non-invasive methods of material analysis are preferred.
For example, in security settings, efficiency concerns dictate use of non-invasive identification techniques such as x-ray analysis. More recently, nuclear magnetic resonance (NMR) has been used in security settings to identify unknown substances by measuring common NMR parameters and comparing these parameter values to known parameter values of known substances. In some instances, however, the measured NMR parameter values are not sufficient to positively identify an unknown substance. Current NMR analysis techniques can also be too time intensive to be useful in high-throughput security settings.